There's a big discussion going on in our league about tokens.
In a tournament do you have to use the real card tokens or can you replace them with something else? Say like a dice or so.
We couldn't find any rules about this so we decided to take the real cards as the only thing legal. Because the card tokens are in the serie.
You can use anything, as long as it can be exhausted/ready and stunned/unstunned. So a coin doesn't work well because it can't show all 4 possible positions. Regular playing cards, or even feature cards from other missions, work well. (Something to do with all those Bigfoots you may have)
The cards are there to be a fun tool for players and collectors, not a requirement. They take the place of a mission/feature card in the packs.